Easy open carton construction and blank therefor



Sept. 24, 1968 M. w. KUCHENBECKER 3,402,876

EASY OPEN CARTON CONSTRUCTION AND BLANK THEREFOR 6 Sheets-Sheet 1 Filed April 10, 1967 FIG.3

INVENTOR. MORRIS W. KUCHENBECKER Sept. 24, 1968 M. w. KUCHENBECKER 3,402,876

EASY OPEN CARTON CONSTRUCTION AND BLANK THEREFOR' Filed April 10, 1967 6 Sheets-Sheet 2 FIG. 5 s4 /eov ee ((52 ea v as -36 36 -36 I l 40 INVENTOR. 37 52 42 50 W 54 MORRIS w. xucnsnazcxan p 1968 M. w. KUCHENBECKER 3,402,876

EASY OPEN CARTON CONSTRUCTION AND BLANK THEREFOR Filed April 10, 1967 6 Sheets-Sheet 3 INVENTOR. MORRIS W. KUCHENBECKER P 1968 M. w. KUCHENBECKER 3,402,876

EASY OPEN CARTON CONSTRUCTION AND BLANK THEREFOR 6 Sheets-Sheet 4 Filed April 10, 1967 FIG. n

94 F'G. l2

INVENTOR MORRIS W. KUCHENBECKER Sept- 1968 M. w. KUCHENBECKER 3,402,876

EASY OPEN CARTON CONSTRUCTION AND BLANK THEREFOR Filed April 10, 1967 6 Sheets-Sheet 5 6 FIG I5 :04 (4 {I06 [94 (I08 f loo 83 s2-- 9e 9e I04 FIGJG I08 H6 106 :14 ,94

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EASY OPEN CARTON CONSTRUCTION AND BLANK THEREFOR Filed April 10, 1967 6 Sheets-Sheet 6 0 mm mm f m u 1 l o M L 6 6 M n B 2 m u v I 6 a B n Y m f O 4 {I 6 n B ar d T v G a T \ll f J J m 72 ls m m m G w F FIG. l8

United States Patent 3,402,876 EASY OPEN CARTON CONSTRUCTION AND BLANK THEREFOR Morris William Kuchenbecker, Neenah, Wis., assignor to American Can Company, New York, N.Y., a corporation of New Jersey Filed Apr. 10, 1967, Ser. No. 629,584 17 Claims. (Cl. 229-51) ABSTRACT OF THE DISCLOSURE An improved end construction for an easy open carton in which the body wall has a folded ,over extension so as to provide resistance to torsion in the course of opening the carton by means of a tear strip. The upper wall is either notched or provided with cut scores to enable the extension member to fold backwardly and inwardly upon the body wall without binding. The bottom of the carton may be either rectangular or circular with the top always being circular. Vertical corner score lines provide rigidity to the rectangular base and a gradual transition from the rectangular bottom shape to the circular shape of the top. Intermediate vertical score lines permit the blank to be shipped flat.

This invention relates to easy open carton constructions and more particularly to an improved end construction for an easy open carton whereby the carton may be opened without difliculty.

Heretofore, easy opening devices have been utilized such as is disclosed in Helms and Kuchenbecker Patent 3,227,054, which is suitable for opening cartons formed from a laminated blank construction. One difilculty has been observed in that the upper portion of the carton tends to twist with respect to the lower portion when the tear strip is being pulled off. This is especially noticed when the tear strip has been pulled somewhat beyond the half way point in which position the body wall has become progressively weaker. It is not a sufficient answer to this problem simply to increase the overall thickness of the body wall of the carton because the attractiveness of the carton from a cost viewpoint becomes substantially lessened.

Accordingly, it is a feature of the present invention to provide an improved end construction for an easy open carton whereby the body wall may be strengthened without substantially increasing the cost of the carton. This is accomplished according to the present invention by providing a fold over extension or skirt which when folded backwardly and inwardly upon an end of the body wall prevents the body from twisting. It also gives additional thickness and thereby imparts strength to the board because it makes it possible for the can end to obtain a better purchse or grip on the body wall.

An additional benefit derived from the disclosed construction is that it gives strength to the body wall just below the cover rim which is the area subjected to the wearing of one can end on an adjacent body wall, a problem frequently referred to as chime riding.

Significant economies can also be provided by eliminating one of the metal ends from the container. This is ac complished in certain embodiments of the present invention by providing a folded over rectangular base for the carton with means provided to enable the body wall to merge smoothly and gradually from the rectangular base into a circular upper end. Thus, a single circular metallic can end may be employed for the container. This is accomplished in the present invention by providing four vertical corner score lines which permit the transition to occur gradually from the rectangular bottom of the container to a circular top.

One additional feature of the invention is to provide the body wall of the container with vertical score lines which extend throughout the entire length of the blank so as to permit the carton to be shipped flat. It has been found that in order to obtain a satisfactory set up of the carton the location of the vertical scores permitting collapse of the blank is critical. Specifically, it has been found that the vertical scores must be placed intermediate the vertical corner scores so as to permit the container to be set up with relative ease.

Accordingly, it is a primary object of the present invention to provide an improved end construction which provides adequate torsion resistance to enable the use of a tear strip on a paperboard carton.

It is another object of the present invention to provide an easy open carton construction having a rectangular 7 base and circular top.

It is still another object of the present invention to provide a blank construction which may be shipped fiat and which may be easily erected to provide a rectangular base and circular top.

It is still a further object of the present invention to provide an end construction which provides improved resistance to wear immediately beneath the top closure member.

These and other advantages of the present invention will become apparent from the detailed specification which follows and by reference to the accompanying drawings in which:

FIGURE 1 is a perspective view of an easy open carton construction of the present invention prior to placing on the top closure member;

FIGURE 2 is a perspective view of the easy open carton construction illustrated in FIGURE 1 with the top closure member in place;

FIGURE 3 is a fragmentary perspective view of the container of FIGURE 2 showing the opening thereof by means of a tear strip;

FIGURE 4 is an exploded fragmentary perspective view of the container of FIGURE 2 after the tear strip has been removed;

FIGURE 5 is a top plan view illustrating the inside of a blank used to make the container body and bottom of the carton of FIGURE 1;

FIGURE 6 is a top plan view illustrating the outside of the blank used to make the body and bottom of the carton of FIGURE 1;

FIGURE 7 is a perspective view of the blank of FIG- URES 5 and 6 formed into a tube and then knocked down into a flattened form;

FIGURE 8 is a fragmentary perspective view illustrating the formation of the rectangular bottom of the blank shown in FIGURES 5 and 6;

FIGURE 9 is a fragmentary perspective view illustrating the completely formed 'bottom of the carton blank of FIGURES 5 and 6;-

FIGURE 10 is a perspective view of a completely formed container made in accordance with another embodiment of the subject invention;

FIGURE 11 is a fragmentary cross sectional view taken along lines 11--11 of FIGURE 10;

FIGURE 12 is a fragmentary cross sectional view taken along lines 1111 of FIGURE 10 with the tear strip being opened;

FIGURE 13 is a fragmentary perspective view taken along lines 13-13 of FIGURE FIGURE 14 is an enlarged fragmentary cross sectional view illustrating typical materials used in the formation of the blanks used in the present invention;

FIGURE 15 is a top plan view of the outside of the blank construction used in making the body wall of the container in FIGURE 10;

FIGURE 16 is a top plan view of the inside of the blank construction used in making the body of the container in FIGURE 10;

FIGURE 17 is a top plan view of the outside of a blank illustrating a modified version of the present invention; and

FIGURE 18 is a top plan view of the inside of the blank illustrated in FIGURE 17.

Referring now to FIGURES l and 2 of the drawings, there is illustrated a carton, indicated generally at 20, formed with a rectangular base, indicated generally at 22. Carton 20 has an easy open tear strip 24 with the specific tear strip material being shown at 26 in FIGURE 5. The tear strip 24 is provided with a finger tab 28 to facilitate grasping of the tear strip. In the formation of tear strip 24 there is provided at least one line of weakness 30 which is shown to be substantially parallel to the base 22 of carton 20. A tapered line of weakness 32 merges from the joinder of the finger tab 28 with side 74 of carton 20 to the line of weakness 30.

In the formation of rectangular base 22, a bottom score line 34 is employed. Further, in order to facilitate shaping of a rectangular base 22 there are provided four vertical corner score lines 36. It will be observed that vertical corner score lines 36 intersect and pass through bottom score line 34 and extend from the base 37 of the blank 20 to a point slightly less than the midpoint of blank 20. The length of vertical corner score lines 36 is a function of the height and total capacity of the container.

In order to permit the container to be knocked down and shipped flat, two vertical score lines 38 are provided which extend from the base 37 of carton 20 to the top thereof. It is important that vertical score lines 38 shall not coincide with vertical corner score lines 36 in order to permit the container to be set up with relative ease. That is, if the score lines 38 coincide with vertical corner score lines 36 or are closely adjacent thereto, the rectangular cross section for the carton will predominate and it will be difiicult to afiix a circular top. Preferably, vertical score lines 38 are midway between opposed pairs of vertical score lines 36 when the carton is erected as illustrated in FIGURE 2.

The bottom score line 34 and its intersection with the four vertical score lines 36 combine to provide a series of bottom folding flaps 44, 46, 48, and 52. In order to provide a more secure bottom closure, the center bottom folding flap 48 is provided with a tongue extension 54 to assist in providing a greater overlap of bottom folding flap 48 with respect to bottom folding flaps 44 and 52. Additional assistance in the formation of a rectangular bottom construction is provided by pairs of V-shaped scores 40, 42 which permit the collapse of alternate adjacent bottom folding flaps 46, 50 as can best be seen in FIGURE 8 to provide the rectangular bottom closure disclosed in FIGURE 9.

Referring again to FIGURES 5 and 6, an upper score 56 parallel to the base 37 of carton 20 defines an extension or skirt, indicated generally at 58. A series of notched or cut out portions 60, 62 are utilized to permit the extension or skirt 58 to be folded backwardly and inwardly of the container, as shown best in FIGURE 1, in order that the extension or skirt 58 will not bind in this folding operation. The notched or cut out portions 60, 62 in extension or skirt 58 defines a series of flaps 64, 66 and 68. Although only two notched or cut out portions 60, 62 are illustrated in FIGURES 5 and 6, any convenient number of these notched or cut out portions may be used to insure that the extension or skirt 58 will not bind when it is folded into the position of FIGURE 1. It will be noted (FIGURES 3 and 4) that in opening the container by removal of the tear strip, the skirt 58, which was originally attached to the container body, is separated from the body and is removed as an integral portion of the top structure. In its dependent relationship from the cover portion, the skirt now serves to facilitate reclosure of the carton, should such action be desirable in a particular situation.

FIGURES 2, 3 and 4 illustrate a conventional metal can end 70 placed upon the upper end of carton 20. Carton 20 has vertical end portions 72 and 74 which overlap to define the vertical seam as is illustrated in FIG- URES 7, 8 and 9.

As will be explained in greater detail later, the blank construction comprises a laminated construction. The inner and outer laminates thereof are of a heat sealable material, such as polyethylene, so that overlapping flaps 48, 44 and 52 may be heat sealed together to effect the bottom closure illustrated in FIGURE 9.

Referring now to FIGURE 10 of the drawings, there is illustrated another embodiment of the present invention in which both the top and bottom of the carton are shown to be circular. The container illustrated in FIGURE 10 uses the blank construction shown in fiat position in FIG- URES 15 and 16. The blank indicated generally at is shown to have vertical edges 82, 83 which overlap to provide a conventional overlapped heat sealed longitudinal seam. Once again the carton is illustrated to have an easy open tear strip 84 with the specific tear strip material being indicated at 86. As in the previous embodiment, the tear strip 84 is provided with a finger tab 88 and a line of weakness 90 which parallels the base of carton blank 80 and bottom score line 95. A tapered line of weakness 92 merges from the joinder of the finger tab 88 with side 82 to the line of weakness 90. The blank 80 is provided with a pair of vertical score lines 98 so that the blank can be flattened in the manner in which the blank 20 was flattened and depicted in FIGURE 7.

The blank 80 is provided with top and bottom extensions, indicated generally at 100 and 101, by means of score lines 94 and 95 which parallel the tear strip 84 and the line of weakness 90. A series of top folding flaps 104, 106 and 108 are defined in the top extension by virtue of the notched or cut out portions 114, 116 in the top extension 100. Similarly, a series of bottom folding flaps 105, 107, and 109 are defined in the bottom extension 101 by virtue of the notched or cut out portions 115, 117 in the bottom extension 101. The top folding flaps 104, 106 and 108 as well as the bottom folding flaps 105, 107 and 109 are folded backwardly and inwardly to form a reinforced end construction similar to that disclosed at 58 in FIGURE 1.

Conventional metal can ends 118 and 119 are illustrated in FIGURES 10, 11, 12 and 13 in assembled relationship with carton blank 80.

FIGURE 14 illustrates the typical laminated material used in the various embodiments of the present invention. Thus, there is shown an outer coating of polyethylene overlaying and securing a tear strip to a layer of aluminum foil which in turn is secured by a suitable adhesive to a paperboard body ply. An inner layer of polyethylene permits the overlapping portions of the blanks to be heat sealed to one another.

Referring now to FIGURES 17 and 18 there is illustrated a modified form of carton blank, indicated generally at 120. The carton blank 120 is shown to have an easy open tear strip 124 with the specific tear strip material being illustrated at 126 in FIGURE 18. As in the previous embodiments, the tear strip 124 has a finger tab 128 and at least one line of weakness 130 which is parallel to the base 137 of the carton blank 120. Scores 140 and 142 combine to form a composite V-shaped score configuration similar to that provided in FIGURES 5 and 6 and the bottom folding flaps 144, 146, 148,

150 and 152 function in the same manner as do bottom folding flaps 44, 46, 48, 50 and 52 in FIGURES 5 and 6. Again, the center bottom folding flap 148 has an extension or tongue 154 to enable an adequate bottom seal to be obtained when bottom folding flap 148 overlies flaps 152 and 144. The vertical edges of the blank 120'are shown at 174 and 172 with these edges arranged to'provide the lapped longitudinal seam in the manner that the edges 72 and 74 do in theblank construction of FIGURES 5 and 6.

The cartonblank 120, however, is provided-with a series-of closely-spaced knife cuts to produce a knife out line 156 which provides an extension or skirt 158. Although the width of the closely-spaced cut scores is exaggerated in FIGURES 17 and 18, they do nevertheless provide a sufficient weakening of the fibers in the carton blank 120 to permit the extension 158 to be folded down inside the body wall without binding in a manner similar to that illustrated for the extension or skirt 58 in FIG- URE 1.

The skirt 158 is arranged and dimensioned to KChlCVC concentric relationship with respect to the outer wall of the carton blank 120 when the container is formed. The connections between the body of the container and the skirt 156 are adapted to distort slightly and at least partially rupture in order to accommodate the difference in diameter between the skirt and the container body when the blank is formed into a cylinder with the skirt in its inwardly folded position.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description, and it will be apparent that various changes maybe made'in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing its material advantages, with the forms hereinbefore described being merely preferred embodiments thereof.

What is claimed is:

1. An improved end construction for a carton comprising a carton body wall, a tear strip aflixed to an upper portion of said carton body wall, said body wall having an extension member folded backwardly and inwardly upon an end portion of said carton body wall, and said endportion of said body wall and said extension adapted tobe engaged tightly by a metallic carton end whereby said extension provides torsional rigidity to said carton body wall when said tear strip is removed from said carton body wall.

' 2. An improved end construction for a carton as defined in claim 1 wherein said carton body wall is provided with a line of weakness between said carton body wall and the extension thereof so as to facilitate the folding ofsaid extension.

-. 3. An improved end construction for a carton as defined iniclaim 2 wherein said extension member of said carton body wall is provided with a plurality of notched portions to permit said extension member to be folded backwardly and inwardly upon said end portion of said carton body wall without binding.

4. An improved end construction for a carton as defined in claim 2 wherein said line of weakness between said carton body wall and said extension thereof consists of a series of closely-spaced cut scores.

5. A blank construction for an easy open carton comprising a main body having a substantially rectangular shape, a bottom score line being substantially parallel to and spaced from the base of said blank, said bottom score line being foldable at the base of the carton to form a substantially rectangular bottom closure, four vertically extending corner score lines each intersecting said bottom score lines and being foldable at each corner of the carton, a line of weakness parallel to said bottom score line being foldable at the top of said carton, an extension member being foldable about said line of weakness backwardly and inwardly upon the upper portion of said main body of said blank, a tear strip. member afiixed to said main body of said blank adjacent and parallel to said line of weakness which parallels said bottom score line.

6. A blank construction for an easy opening carton as defined in claim 5 wherein said extension member is provided with a plurality of notched portions to permit said extension member to be folded backwardly and inwardly upon said main body of said blank without binding.

7. .A blank construction for an easy opening carton as defined in claim 5 wherein said line of weakness which parallels said bottom score line consists of a series of closely-spaced cut scores.

8. A blank construction for an easy open carton as defined in claim 5 wherein said four vertically extending corner score lines extend from the bottom of said blank to approximately the midpoint of said blank whereby a substantially rectangular base may be formed from said carton and a substantially circular top.

9. A blank construction for an easy opening carton as defined in claim 5 wherein two additional vertically extending score lines are positioned substantially midway between opposed pairs of said corner score lines and extend from the bottom of said blank to the top thereof whereby said blank may be formed into a tube and shipped flat.

10. A blank construction for an easy opening carton as defined in claim 6 wherein two additional vertically extending score lines are positioned substantially midway between opposed pairs of said corner score lines and extend from the bottom of said blank to the top thereof whereby said blank may be formed into a tube and shipped flat.

11. A blank construction for an easy opening carton as defined in claim 7 wherein two additional vertically extending score lines are positioned substantially midway between opposed pairs of said corner score lines and extend from the bottom of said blank to the top thereof whereby said blank may be formed into a tube and shipped flat.

12. A blank construction for an easy opening carton as defined in claim 8 wherein two additional vertically extending score lines are positioned substantially midway between opposed pairs of said corner score lines and extend from the bottom of said blank to the top thereof whereby said blank may be formed into a tube and shipped flat.

13. A blank construction for an easy opening carton as defined in claim 5 wherein said four vertically extending score lines extend to the base of said blank to define with said bottom score line a plurality of bottom closure flaps and wherein a pair of alternate adjacent flaps formed thereby are provided with V-scores to permit overlapping of the remaining alternate adjacent flaps so as to form a substantially rectangular bottom closure for said carton.

14. A blank construction for an easy opening carton as defined in claim 6 wherein said four vertically extending score lines extend to the base of said blank to define with said bottom score line a plurality of bottom closure flaps and wherein a pair of alternate adjacent flaps formed thereby are provided with V-scores to permit overlapping of the remaining alternate adjacent fiaps so as to form a substantially rectangular bottom closure for said carton.

15. A blank construction for an easy opening carton as defined in claim 7 wherein said four vertically extending score lines extend to the base of said blank to define with said bottom score line a plurality of bottom closure flaps and wherein a pair of alternate adjacent flaps formed thereby are provided with V-scores to permit overlapping of the remaining alternate adjacent flaps so as to form a substantially rectangular bottom closure for said carton.

16. A blank construction for an easy opening carton as defined in claim 8 wherein said four vertically extending score lines extend to the base of said blank to define with said bottom score line a plurality of bottom closure flaps and wherein a pair of alternate adjacent flaps formed thereby are provided with V-scores to permit overlapping of the remaining alternate adjacent flaps so as to form a substantially rectangular bottom closure for said carton.

17. A blank construction for an easy opening carton as defined in claim 9 wherein said four vertically extending score lines extend to the base of said blank to define with said bottom score line a plurality of bottom closure flaps and wherein a pair of alternate adjacent flaps formed thereby are provided with V-s cores to permit overlapping of the remaining alternate adjacent fiaps so as to form a substantially rectangular bottom closure for said carton.

References Cited UNITED STATES PATENTS 1,916,519 7/1933 ,Madsen et al 229 21 1,963,994 6/1934 Herrmann 229 51 2,318,655 5/1943 Zalkind 22937 2,375,621 5/1945 Burns 220 5 2,755,983 7/1956 Ringler 2 229-21 2,858,057 10/1958 Mullinix 229 51 3,142,433 7/1964 Balocca 229-51 3,269,640 8/1966 Arneson=-- 229-21 3,300,118 1 1/1967- Owens 229 -51 DAVIS T. MQORHEAD, Primary Examiner. 

